The worlds biggest private yacht is under construction

Looking for a boat that has seven decks worth of space, 15 staterooms, room for a helicopter or two, and can carry your own private submarine? All this can be yours if you have $270 million for the worlds most expensive yacht.

Soundings Online features a profile the Hull 6154, the biggest privately-owned yacht that is under construction by Fincantieri in Genoa, Italy.

Who is such a big yacht for? The owner is currently unknown, but rumored to a Russian billionaire.